The calculated distance (air line) between Siem Reab and Tbeng Meanchey is approximately 167 miles respectively 268 kilometers.
By car or train, the actual journey to Tbeng Meanchey is certainly longer, as only the direct route (as the crow flies) between Siem Reab and Tbeng Meanchey has been calculated here.
Air line (approximately)
268 kilometers
145 nautical miles